El Mundo de Birch
A Spanish teacher's class wiki, this page in particular is of interest to Spanish teachers. The author includes a database of hundreds of Spanish-language songs searchable by country of origin, grammar features of the lyrics, artist names, and song names. He also includes a worksheet for music appreciation which prompts students to listen for specific sounds, words, and instruments.

Teaching With Technology
This fabulous blog was created by Carrie Bradley and Nikki Wagner, both teachers. Carrie and Nikki created the wiki for other teachers. It includes ideas for using Web 2.0 tools in the classroom as well as tutorials.

Cool Tools - Web 2.0 Tools
An extensive list of tech tools, along with where to get them, how to use them, and what to use them for.

ISTE Tech Standards Wiki
Resources for implementing ISTE standards, as well as Web 2.0 tools.

50 Ways to use Web 2.0 Tools to tell a story

Cool Tools for Schools
An extensive wiki with Web 2.0 tools sorted by category.

Educause
Lots of information and tutorials on using Web 2.0 tools in the classroom, including tricky topics like Creative Commons and web publishing for students.